Well drilling bit set



De@ 15, 1931.. P. CHISTENSEN 1,836,703

WELL DRILLING BIT SET Dec, 15, 1931. v P. cHRlsTE'Nsl-:N A18`36"Q3 WELL DRILLING BIT SET I Filed Sept, l1, 1930 2 Sheets-Sheet 2 Patented Dec. 15, 1931 UNITED STATES PETER CHRISTENSEN, OF KINGSVILLE, TEXAS WELL DRILLING Brr snr Application led September 11, 1930. Serial No. 481,302. l

This invention relates to a well drilling bit combination.

A prime object of the invention is to provide a means whereby a bit may be so assooiated with the usual well casing that the latter constitutes the stock of the bit, overcoming the necessity of using a separate stock or of using casing after operation of the bit.

It is further aimed to providev a novel means forming the bit consisting of a plurality of elements and mounting means, in combination with a shoe for attaching the same to the casing. Y

It is also aimed to provide a novel construction which may be readily lished.

In addition it is aimed to provide a novel tool to permit disconnection of the casing and shoeafter removal of the bit.

20 Various additional objects and advantages will become apparent from a consideration of the description following taken in connection with accompanying drawings illustrating an operative embodiment.

In said drawings Figure 1 is a view in vertical section illustrating the invention,

Figure 2 is a vertical sectional view taken on the line 2-2 of Figure 1,

Figure 3 is a bottom plan view of the invention, Y Y

Figure 4 is a cross sectional view taken on the line 4 4@ of Figure l,

Figure 5 is a view similar to Figure 1 but showing a fishing tool applied,

Figure 6 is a cross sectional view taken on the line 66 of Figure 5,

Figure 7 is a vertical sectional view showing the use of a shoe-removing tool, and

Figure 8 is a vertical sectional view taken on the line 8-8 of Figure 7. Y

Referring specifically to the drawings, 10 designates well casing which in use is usually made up of a number of detachable sections as well understood in the art. According to the present invention, such casing constitutes the stock of the bit and hence a separate stock for the bit is unnecessar and the casing does not have to be applied a ter boring and which overcomes many of the difficulties experi- Vwhich may be of rubber o r any other enced in well drilling, such as cavinginof the walls of thebore. 7 l v At thelower end oi" the casing, ,a shoe 11 is detachably connected by screw threads as at 12, the same being of cap form so as to have a transverse wall `13. The shoe has two slots at 14'which extendA across thefwall L13 and partly up the side of the shoe. i Two cutters or bitmembers areprovided as at 15 each of which has an elongated slot 16 through which a securing pin 17 passes. The pin 17 is carried by a sleeve 18 and is adapted to be removed therefrom in order that the bit may be detached, when necessary, from the'sleeve 18v 'when the saine isV out of 55 the well. Y Said pin 17 looselyv engages Vin openings 19 in the` wall of tubeV or sleeve 18' and it isnormally heldvagainst displacement' by a collar 20 which is screw threaded as at 21 to the sleeve 18 and crosses the endsof such pin. l. j

The cutting portions 22 "of the bit members 15 may be of any desired form butfas shown they extend belowthe shoe and also laterally or diametrically 'beyond Vthe same.

Attention is called to the factlthat the bit members at one side thereof are stepped to provide various shoulders at diiferent` elevations as at'23, 24 and 25, to be engaged, respectively by the shoe, casing 10 and tube 18 and its collar, so that the full weight of the string of casing will rest Von the bit to insure effective cutting whenV in use. A f

The sleeve,l 18 is suitably centered in the casing; 10, guided, `and constructed so `that oil'or fluid may pass the same.` To this end, a plurality of washers -26 may be screw threaded onto the upper portion of the tube, and clamp a suitable `washer 27 therebetween,

Ie-j ferred material, the elements 26 and 27'pref-- .erably being peripherallygrooved or notched as` at 28 to permlt passage of Afluid past the same. 2 l i r, Inor'lerthat'the sleeve 18 may be engaged 9"* by 'a fishing tool. in order to removethe same? and the bit, a spear or similarly shaped head 29 is provided thereon. Itwill be realized that the Aslots 16 inuse are at an angle to each other and that as'the sleeve 18 is elevatedjtlev 'ma A detachable head 32 is screw threaded at4 33 on the lower end of body 30 and the same has a conical bore portion 34 and a laterally disposed shoulder 35 directly above the same. upon which latch plates 36 normally rest in a horizontal position, such plates 'being hinged on horizontal axes 37 to the headY 32. Such. latches 36 are capable of vertical movement as the fishing tool. is lowered over the spear 29, after which the latches will automatically move to horizontal position and engage under theV shoulder at the base of the `spear 29 vas shown in Figure 5, so that raising movementv o n the cable 31 will extract the sleeve 18 and boring members.

After the partsihave been removed from theV shoe andv casing, at the end of drilling operations, the tool of Figure 7 is used to disengage the shoe from the casing. This tool may comprise a rod or tubing 38 and at the lower end thereof have a plurality of bits 39 pivoted thereto as at 40 and adapted to enter the slots 14. In such position, turning of rod 38 will turnV the shoe 11 relatively to the casing and thus detach it.

1. A tool of the class described compris-- ing a tube, cutter means, means within the tube removably7 suspending the cuttermeans,

and said cutter means being overlapped and rested upon by the tube and a collar movably connected in line with the second mentioned means.

2. A tool of the class described comprising a tube, a shoe thereon having slots, a pair of cutters extending through the slots and rested upon by the tube, said cutters having elongated slots disposed at an angle to each other in operative position, a sleeve within the tube,said sleeve having a pin removably disposed in said slots for the purpose specified and a collar movably connected to the sleeve inline With the pin.

3., Atool of the class described comprising a, tube, a shoe thereon having slots,.a pair of cutters extending through the slots and rested upon by the tube, said cutters having elongated slots disposed at an angle to each other in operative position, a sleeve within the tube, said Ysleeve having a. pin disposed in said slots for thepurpose specified, saidpinibeing removable, anda collar detachably connected to the sleeve in line with the pin, means on the sleeve to engage the tube to center the sleeve.

In testimony whereof I affix my signature.

PETER CHRISTEN SEN. 

